Water pistol



FIG. 1 is an upper perspective view of the water pistol showing my design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a side view thereof;

FIG. 5 is an opposite side view thereof; and,

FIG. 6 is a top view thereof. 

I claim the ornamental design for a water pistol, as shown and described. 